Electric meter.



, J. HARRIS.

I ELECTRIC METER.

A'PPLIOATION FILED MAY 3, 1909. RENEWED JULY 6, 1910. 970,498. PatentedSept. 20, 1910.

2 SHEBTB-BHBBT 1.

WITNESSES: INVEN-TOR.

A TTORN E V J. HARRIS.

ELECTRIC METER.

, APPLICATION FILED MAY3, 1909. RENEWED JULY 5, 1910.

970,498. Patented Sept. 20, 1910.

2 SHEETS-SHEET 2.

WITNESSES: INVENTOR.

ATTL

UNITED STATES PATENT OFFICE.

JESSE HARRIS, OF LA FAYETTE. INDIANA, ASSIGNOR TO DUNCAN ELECTRIC MANU-FACTURING COMPANY, OF LA FAYETTE, INDIANA, A CORPORATION OF ILLINOIS.

ELECTRIC METER.

Specification of r latcnt. Patented Sept. 20. 1910.

Application filed May 3, 1909, Serial No. 493,543. Renewed July 5, 1910.Serial No. 570,898.

To all whom it may concern:

Be it known that I, .Iussn I'IARRIS, citizen of the United States,residing at La Fayette, in the county of Tippecanoe and State ofIndiana, have invented a certain new and useful Improvement in ElectricMeters, of which the following is a full, clear, concise, and exactdescription, reference being had to the accompanying drawings, forming apart of this s )ecification.

My invention relates to electric meters of the class in which a liquid,preferably mcrcury, is employed for conveying current to and from thearmature, which is immersed in, or is in contact with, the liquid.

It is one of the objects of my invention to provide means whereby theliquid may be securely retained during shipment of the meter to preventloss thereof in transit, and the invention has for another of itsobjects the provision of improved means for compensating for friction inthe bearings or working parts of the instrument.

I will set forth my invention by a description of the preferredembodiment thereof, shown in the accompanying drawings, and Will moreparticularly point out the invention in the claims.

In the drzuvings-Jfigurc 1 is elevation on line 1 l of Fig. 2, of ameter constructed in accordance with my invcn tion, the circuitconnections of the meter being diagrammatically indicated. Fig. .2 is aplan view of the structure. shown in l ig. l, the damping-disk beingomitted. lg. 25 is a sectional clcvation on line 23 3 of Fig. 2. Fig. 4are views of one form of valve mechanism that enters into the device ofmy invention.

Like parts are in licatcd by similar characters ol. reference throughoutthe different figures.

In the embodiment of the invention illustrated, I have indicated acounting-train a in gear with a meter-shaft I) having a stopbearing 0 atits lower end and a lateraltln'ust-bcaring d at its upper end, theshat'tI) carrying a damping disk 0 rotating in the fields of the permanentmagnets f, the shaft of the meter also carrying a disk-arimiture l Theshaft [/1 also carries a flotation-clemcnt /L that serves to buoy thearmature and the meter-shaft, the elements and It being located within aliquid or mercury chambcr formed by the ttHSCll'lblCtl elements asectional 1 relation with a main of the distribution circuit with whichthe meter is associated, the circuit including the bath of mercury beingtracmible from the source of current at to a terminal n, through themercury and the armature r in the mercury, to the terminal 0, thencethrough the series field winding 1) to the load (1. The meter, whenconstituting awatt meter, also includes pressure circuit that containsthe pressure winding-r. 'lhc windings y) and r are provided with amagnetic core a, dcsirabl of horse-shoe form, whose free polar emf; arein a plane parallel with the armature-disk g and are preferablypresented at right-angles to the plane of said :lllllulUFO-disk. Thereis localcd above the disk g, a body of iron 1% which cooperates with thecore .9 to afford a circuit for the lines of force set up by thewindings 71 and 1'.

As is well known by those skilled in the art, it is very dillicult toship mercury mclcrs owing to the fact that the mercury is very liable.to work out through the cracks and small openings encountered in thenu-rcury chamber and the parts coulmunicating therewith. l. have avoidedthis objectionable feature in mercury meters by providing a storagechamber u. H! the meter casing, which storage chamber is adapted to fromthe storage chamber w to the meter mercury chamber that contains thearmature. In the preferred embodiment of the invention, the storagechamber 1/ is located above the armature I/ .and the meter mercurychamber containing said armature, so that. when the meter has arrived atits destination, it will be sutlicicnl. merely to turn the valve w to anopen position, whereupon the mercury will llow into the meter mercurychamber properly to i |'nmcrse thc armature and place the meter inworking condition. In the preferredpractice of my invcntion, the storagechambcr a is only sullicicnlly large to contain the mercury that isneeded in the meter, so that during shipmcnt. there is no space withinthe storage chamber u that is unfilled by mercury. In this Way them'rcury will not in its agitation become intermixed with the air to formdross.

In order to compensate for friction, I provide a switch-arm m connectedwith one side of the distribution circuit, preferably through thepressure-winding r, and contact-buttons 3 connected with the other sideof the distribution circuit through the mercury within the armaturechamber. The conductors 2 that connect the buttons 3 electrically withthe mercury, are tightly inclosed within the bores of small metallictubes 2 that are passed through, but are insulated from, the iron-diskt, these tubes contacting at their lower ends with the mercury in themercury chamber. The tubes .2 are located varying distances from each ofthe terminals 01 and 0, so that more or less of the mercury is includedin serial relation with the pressure winding 1 of the meter, wherebyfriction may be compensated for, this result being gained withoutdisturbing calibration of the meter, inasmuch as the resistancevariation due to the varying quantities of mercury that may be includedin circuit by the switch 0;, is negligible. \Vhen the meter is thusorganized, the series portion, which operates to effect rotation of themeter, is included in circuit when. a load is in operation. A sufiicientportion of the mercury that is included in the series circuit, is, bymeans of the switch it, always in circuit, whether or not the load ispresent or absent, to cotiperate with the pressure circuit of the meter,almost to start,

the meter, this starting tendency being regulated to counterbalance thefriclioin'so that when a loadportion is included in circuit, the meterwill. operate. A button 1 is also associated with the switch :0, thislatter button being connected directly with the same main with which thebuttons 3/ are connected, the button y, llOWGVCI', not depending uponthe mercury for its connection with said main. The button ef has aconnection with said main through the entire bath of mercury, thecircuit being traced, when the switch-arm a; rests upon the button 3from the pressure-winding a and the. main of the distribution circuitconnected directly therewith, through the switch-arm :0, the button 3the lll'li'iillal o, the mercury, the terminal /1., to the conn ianionmain of the distribution circuit. When the greatest offset to frictionis to be provided, the switch-arm 56 is placed in connection with thebutton 19/ decreasing degrees of friction compensation being afiorded asthe switch-arm m successively encounters the buttons as said switcharmis moved toward the left, said switcharm, when engaging the button y,includ ing none of the mercury in circuit, there then being no frictioncompensation.

\Vhile I have herein shown and particularly described the preferredembodiment of my invention, I do not wish to be limited to the preciseconstruction shown, as changes may readily be made without departingfrom the spirit of my invention.

llaving thus described my invention, I

claim as new and desire to secure by Letters Patent the following 1. Anelectric meter including an armature, a liquid-containing chamberinclosing said armature, a storage chamber serving to hold the liquid tobe used in' the aforesaid chamber, apassage intervening between saidchambers, and a valve in said passage for preventing or permitting flowbetween said chambers.

2. An electric meter including an armature, a liquid-containing chamberinclosing said armature, a storage chamber serving to hold the liquid tobe used in the aforesaid chamber, a passage intervening between saidchambers, and means for preventing or permitting flow between saidchan'ibers.

3. An electric meter having current and pressuire-circuits and includinga chamber inclosing the meter arn'iature and holding liquid which formsa part of the current-circuit, and regulable means whereby Varyingportions of the liquid may also be included in the 'pressu1'ecircuit.

4. An electric meter including an armature, a liquid coniaining chamberinclo'sing said ari'nzd-ure, circuit connections whereby the liquid maybe included serially in a distribution circuit, and regulable meanswhereby varying portions of the liquid may be included :ui-ross themains of the distribution circuit.

lu witness whereof, I hereunto subscribe my name this 80th day of AprilA. 1)., 1909.

JESSE HARRIS. llitncsses lhnrr l). i i-nuns, T i a n as lineman.

